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+%%BeginProlog
+50 dict begin
+
+% This is a standard prolog for Postscript generated by Tk's canvas
+% widget.
+% SCCS: @(#) prolog.ps 1.7 96/07/08 17:52:14
+
+% The definitions below just define all of the variables used in
+% any of the procedures here. This is needed for obscure reasons
+% explained on p. 716 of the Postscript manual (Section H.2.7,
+% "Initializing Variables," in the section on Encapsulated Postscript).
+
+/baseline 0 def
+/stipimage 0 def
+/height 0 def
+/justify 0 def
+/lineLength 0 def
+/spacing 0 def
+/stipple 0 def
+/strings 0 def
+/xoffset 0 def
+/yoffset 0 def
+/tmpstip null def
+
+% Define the array ISOLatin1Encoding (which specifies how characters are
+% encoded for ISO-8859-1 fonts), if it isn't already present (Postscript
+% level 2 is supposed to define it, but level 1 doesn't).
+
+systemdict /ISOLatin1Encoding known not {
+ /ISOLatin1Encoding [
+ /space /space /space /space /space /space /space /space
+ /space /space /space /space /space /space /space /space
+ /space /space /space /space /space /space /space /space
+ /space /space /space /space /space /space /space /space
+ /space /exclam /quotedbl /numbersign /dollar /percent /ampersand
+ /quoteright
+ /parenleft /parenright /asterisk /plus /comma /minus /period /slash
+ /zero /one /two /three /four /five /six /seven
+ /eight /nine /colon /semicolon /less /equal /greater /question
+ /at /A /B /C /D /E /F /G
+ /H /I /J /K /L /M /N /O
+ /P /Q /R /S /T /U /V /W
+ /X /Y /Z /bracketleft /backslash /bracketright /asciicircum /underscore
+ /quoteleft /a /b /c /d /e /f /g
+ /h /i /j /k /l /m /n /o
+ /p /q /r /s /t /u /v /w
+ /x /y /z /braceleft /bar /braceright /asciitilde /space
+ /space /space /space /space /space /space /space /space
+ /space /space /space /space /space /space /space /space
+ /dotlessi /grave /acute /circumflex /tilde /macron /breve /dotaccent
+ /dieresis /space /ring /cedilla /space /hungarumlaut /ogonek /caron
+ /space /exclamdown /cent /sterling /currency /yen /brokenbar /section
+ /dieresis /copyright /ordfeminine /guillemotleft /logicalnot /hyphen
+ /registered /macron
+ /degree /plusminus /twosuperior /threesuperior /acute /mu /paragraph
+ /periodcentered
+ /cedillar /onesuperior /ordmasculine /guillemotright /onequarter
+ /onehalf /threequarters /questiondown
+ /Agrave /Aacute /Acircumflex /Atilde /Adieresis /Aring /AE /Ccedilla
+ /Egrave /Eacute /Ecircumflex /Edieresis /Igrave /Iacute /Icircumflex
+ /Idieresis
+ /Eth /Ntilde /Ograve /Oacute /Ocircumflex /Otilde /Odieresis /multiply
+ /Oslash /Ugrave /Uacute /Ucircumflex /Udieresis /Yacute /Thorn
+ /germandbls
+ /agrave /aacute /acircumflex /atilde /adieresis /aring /ae /ccedilla
+ /egrave /eacute /ecircumflex /edieresis /igrave /iacute /icircumflex
+ /idieresis
+ /eth /ntilde /ograve /oacute /ocircumflex /otilde /odieresis /divide
+ /oslash /ugrave /uacute /ucircumflex /udieresis /yacute /thorn
+ /ydieresis
+ ] def
+} if
+
+% font ISOEncode font
+% This procedure changes the encoding of a font from the default
+% Postscript encoding to ISOLatin1. It's typically invoked just
+% before invoking "setfont". The body of this procedure comes from
+% Section 5.6.1 of the Postscript book.
+
+/ISOEncode {
+ dup length dict begin
+ {1 index /FID ne {def} {pop pop} ifelse} forall
+ /Encoding ISOLatin1Encoding def
+ currentdict
+ end
+
+ % I'm not sure why it's necessary to use "definefont" on this new
+ % font, but it seems to be important; just use the name "Temporary"
+ % for the font.
+
+ /Temporary exch definefont
+} bind def
+
+% StrokeClip
+%
+% This procedure converts the current path into a clip area under
+% the assumption of stroking. It's a bit tricky because some Postscript
+% interpreters get errors during strokepath for dashed lines. If
+% this happens then turn off dashes and try again.
+
+/StrokeClip {
+ {strokepath} stopped {
+ (This Postscript printer gets limitcheck overflows when) =
+ (stippling dashed lines; lines will be printed solid instead.) =
+ [] 0 setdash strokepath} if
+ clip
+} bind def
+
+% desiredSize EvenPixels closestSize
+%
+% The procedure below is used for stippling. Given the optimal size
+% of a dot in a stipple pattern in the current user coordinate system,
+% compute the closest size that is an exact multiple of the device's
+% pixel size. This allows stipple patterns to be displayed without
+% aliasing effects.
+
+/EvenPixels {
+ % Compute exact number of device pixels per stipple dot.
+ dup 0 matrix currentmatrix dtransform
+ dup mul exch dup mul add sqrt
+
+ % Round to an integer, make sure the number is at least 1, and compute
+ % user coord distance corresponding to this.
+ dup round dup 1 lt {pop 1} if
+ exch div mul
+} bind def
+
+% width height string StippleFill --
+%
+% Given a path already set up and a clipping region generated from
+% it, this procedure will fill the clipping region with a stipple
+% pattern. "String" contains a proper image description of the
+% stipple pattern and "width" and "height" give its dimensions. Each
+% stipple dot is assumed to be about one unit across in the current
+% user coordinate system. This procedure trashes the graphics state.
+
+/StippleFill {
+ % The following code is needed to work around a NeWSprint bug.
+
+ /tmpstip 1 index def
+
+ % Change the scaling so that one user unit in user coordinates
+ % corresponds to the size of one stipple dot.
+ 1 EvenPixels dup scale
+
+ % Compute the bounding box occupied by the path (which is now
+ % the clipping region), and round the lower coordinates down
+ % to the nearest starting point for the stipple pattern. Be
+ % careful about negative numbers, since the rounding works
+ % differently on them.
+
+ pathbbox
+ 4 2 roll
+ 5 index div dup 0 lt {1 sub} if cvi 5 index mul 4 1 roll
+ 6 index div dup 0 lt {1 sub} if cvi 6 index mul 3 2 roll
+
+ % Stack now: width height string y1 y2 x1 x2
+ % Below is a doubly-nested for loop to iterate across this area
+ % in units of the stipple pattern size, going up columns then
+ % across rows, blasting out a stipple-pattern-sized rectangle at
+ % each position
+
+ 6 index exch {
+ 2 index 5 index 3 index {
+ % Stack now: width height string y1 y2 x y
+
+ gsave
+ 1 index exch translate
+ 5 index 5 index true matrix tmpstip imagemask
+ grestore
+ } for
+ pop
+ } for
+ pop pop pop pop pop
+} bind def
+
+% -- AdjustColor --
+% Given a color value already set for output by the caller, adjusts
+% that value to a grayscale or mono value if requested by the CL
+% variable.
+
+/AdjustColor {
+ CL 2 lt {
+ currentgray
+ CL 0 eq {
+ .5 lt {0} {1} ifelse
+ } if
+ setgray
+ } if
+} bind def
+
+% x y strings spacing xoffset yoffset justify stipple DrawText --
+% This procedure does all of the real work of drawing text. The
+% color and font must already have been set by the caller, and the
+% following arguments must be on the stack:
+%
+% x, y - Coordinates at which to draw text.
+% strings - An array of strings, one for each line of the text item,
+% in order from top to bottom.
+% spacing - Spacing between lines.
+% xoffset - Horizontal offset for text bbox relative to x and y: 0 for
+% nw/w/sw anchor, -0.5 for n/center/s, and -1.0 for ne/e/se.
+% yoffset - Vertical offset for text bbox relative to x and y: 0 for
+% nw/n/ne anchor, +0.5 for w/center/e, and +1.0 for sw/s/se.
+% justify - 0 for left justification, 0.5 for center, 1 for right justify.
+% stipple - Boolean value indicating whether or not text is to be
+% drawn in stippled fashion. If text is stippled,
+% procedure StippleText must have been defined to call
+% StippleFill in the right way.
+%
+% Also, when this procedure is invoked, the color and font must already
+% have been set for the text.
+
+/DrawText {
+ /stipple exch def
+ /justify exch def
+ /yoffset exch def
+ /xoffset exch def
+ /spacing exch def
+ /strings exch def
+
+ % First scan through all of the text to find the widest line.
+
+ /lineLength 0 def
+ strings {
+ stringwidth pop
+ dup lineLength gt {/lineLength exch def} {pop} ifelse
+ newpath
+ } forall
+
+ % Compute the baseline offset and the actual font height.
+
+ 0 0 moveto (TXygqPZ) false charpath
+ pathbbox dup /baseline exch def
+ exch pop exch sub /height exch def pop
+ newpath
+
+ % Translate coordinates first so that the origin is at the upper-left
+ % corner of the text's bounding box. Remember that x and y for
+ % positioning are still on the stack.
+
+ translate
+ lineLength xoffset mul
+ strings length 1 sub spacing mul height add yoffset mul translate
+
+ % Now use the baseline and justification information to translate so
+ % that the origin is at the baseline and positioning point for the
+ % first line of text.
+
+ justify lineLength mul baseline neg translate
+
+ % Iterate over each of the lines to output it. For each line,
+ % compute its width again so it can be properly justified, then
+ % display it.
+
+ strings {
+ dup stringwidth pop
+ justify neg mul 0 moveto
+ stipple {
+
+ % The text is stippled, so turn it into a path and print
+ % by calling StippledText, which in turn calls StippleFill.
+ % Unfortunately, many Postscript interpreters will get
+ % overflow errors if we try to do the whole string at
+ % once, so do it a character at a time.
+
+ gsave
+ /char (X) def
+ {
+ char 0 3 -1 roll put
+ currentpoint
+ gsave
+ char true charpath clip StippleText
+ grestore
+ char stringwidth translate
+ moveto
+ } forall
+ grestore
+ } {show} ifelse
+ 0 spacing neg translate
+ } forall
+} bind def
+
+%%EndProlog